White cell count and diagnosing appendicitis in adults

Date First Published:
March 1, 2000
Last Updated:
May 6, 2003
Report by:
Robert Williams, Clinical Fellow (Manchester Royal Infirmary)
Search checked by:
Katrina Herren, Manchester Royal Infirmary
Three-Part Question:
In [adults with suspected appendicitis] does [a single white cell count] aid [diagnosis]?
Clinical Scenario:
A 24 year old man presents to the Emergency Department with a history and examination consistent with appendicitis. On referral, the duty surgeon requests a full blood count. You wonder whether it will aid the diagnosis.
Search Strategy:
Medline 1966-06/02 using the OVID interface.
Search Details:
[(exp Appendicitis OR acute appendicitis.mp) AND (exp Haematological tests OR exp Leukocyte count or leukocyte count$.mp OR neutrophil count$.mp OR white cell count$.mp OR inflammatory parameter$.mp or white blood count$.mp)] LIMIT to human AND English.
Outcome:
176 papers were found, of which 171 were irrelevant or of insufficient quality for inclusion. The remaining 5 papers are shown in the table.
Relevant Paper(s):
Study Title Patient Group Study type (level of evidence) Outcomes Key results Study Weaknesses
The white cell count in acute appendicitis. A prospective blind study. Miskowiak J, Burcharth F. 1982, Denmark 238 patients (>15) admitted with suspected acute appendicitis Diagnostic test study, blinded WCC>9 000. Histology Sens 84%; Spec 66%; LR+ 1.26; LR- 0.95 No gold standard
Leucocyte count and neutrophil percentage in appendicectomy for suspected appendicitis. Lau WY, Ho YC, Chu KW et al. 1989, Australia 1389 patients (1-87), with right lower abdominal pain, consistent with appendicitis
769 aged 15-65
Non-operative group followed up at 2 and 6 weeks
Diagnostic test study, blinded WCC>10 000 (group 15-65). Histology Sens 88%; Spec 76%; LR+ 3.7; LR- 0.29 No gold standard
Laboratory aid in the diagnosis of acute appendicitis. A blinded, prospective trial concerning diagnostic value of leukocyte count, neutrophil differential count, and C-reactive protein. Dueholm S, Bagi P, Bud M. 1989, USA 204 patients (15-45) admitted with suspected acute appendicitis Diagnostic test study, blinded WCC>11 000 Sens 76%; Spec 74 %; LR+ 2.92; LR- 0.32 No gold standard
WCC>9 000. Histology Sens 83%; Spec 50%; LR+ 1.66; LR- 0.34
Ultrasonography and parameters of inflammation in acute appendicitis. A comparison with clinical findings. Amland PF, Skaane P, Ronningen H et al. 1989, Sweden 110 patients (13-33) admitted with suspected acute appendicitis Diagnostic test study, blinded WCC>10 000. Histology Sens 68%; Spec 69%; LR+ 2.19; LR- 0.69 No gold standard
Diagnostic value of disease history, clinical presentation, and inflammatory parameters of appendicitis. Andersson RE, Hugander AP, Ghazi SH, et al. 1999, USA 502 patients (10-86) admitted with suspected acute appendicitis Diagnostic test study WCC>10 000. Histology Sens 78%; Spec 68%; LR+ 2.44; LR- 0.33 No gold standard
Unblinded
Includes children
Author Commentary:
All the reviewed studies have the weakness of no gold standard diagnostic test against which to compare the non-operative group. Only one study undertakes follow up of its non-operative group, with a single study formally recognising the fact that some abdominal pain, not requiring laparotomy, may have originated from the appendix.

While all the studies seem to produce broad agreement as to the sensitivity and specificity of an isolated white cell count, they are not truly comparable due to the differing selection criteria of patients, age ranges and clinical management. In addition there is a wide prevalence of disease between the groups.
Bottom Line:
A single white cell count is neither sensitive nor specific in the diagnosis of appendicitis.
References:
  1. Miskowiak J, Burcharth F.. The white cell count in acute appendicitis. A prospective blind study.
  2. Lau WY, Ho YC, Chu KW et al.. Leucocyte count and neutrophil percentage in appendicectomy for suspected appendicitis.
  3. Dueholm S, Bagi P, Bud M.. Laboratory aid in the diagnosis of acute appendicitis. A blinded, prospective trial concerning diagnostic value of leukocyte count, neutrophil differential count, and C-reactive protein.
  4. Amland PF, Skaane P, Ronningen H et al.. Ultrasonography and parameters of inflammation in acute appendicitis. A comparison with clinical findings.
  5. Andersson RE, Hugander AP, Ghazi SH, et al.. Diagnostic value of disease history, clinical presentation, and inflammatory parameters of appendicitis.